Process of treating complex ores containing zinc and other volatilizable metals.



PATENTED DEC. 31, 190?. G. M. RICE. I v PROCESS OF TREATING COMPLEX ORES CONTAINING ZINC AND OTHER VOLATILIZABLE METALS.

APPLICATION FILED FEB. 25, 1907.

PROCESS OF TREATIN G COMPLEX ORES Metals,

UNITED STATES PATENT OFFICE.

GEORGE M. RICE, OF WORGESTER, MASSACHUSETTS.

CONTAINING. ZINC AND OTHER METALS.

Specification of Letters Patent.

VOLATILIZABLE Patented Dec. 31, 1907.

Application filed February 25, 1907- Serial No. 359,089.

To all whom it may concern:

Be it known that I,-GEORGE M. RICE, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Process of Treating Complex Ores Containing Zinc and other Volatilizable of whichthe following is a specification, reference being made therein to the accompanying drawings.

The object of my present invention is to aflord a ready means for extracting volatile metals, as for instance zinc, or other metals of a like volatile nature, from their sulfid ores in their raw state, and without a previous roasting or other oxidizing process; also to save certain rare metals ordinarily lost by other processes.

Another object is to provide a method of recovering zinc and other metals of volatilizable nature from their sulfid' ores, taken in their raw state without previous roasting or OXIdJZlIlg, and to save certain non-volatile metals and the sulfur in the form of matte produced in the operation. in treating complex or other zinc ores.

The ores submitted to the process maybe any complex mixtures, as for instance ore carrying the sulfids of zinc, cadmium, mercury, iron, lead, copper, gold, silver, or other metals in greater or less amounts. I find that any or all of the volatile metals contained m such ores can be saved by proper manipulation of the process, while the non-volatile metals, as well as the sulfur contained in the ore mixture, are concentrated in a-matte forIn further utilization.

carryin out In raw ores are first cruzhed to about twenty mesh, more or less, or finer if desired. I then mix with the crushed raw ore finely divided metallic iron, as for instance the drillings or chips produced by iron working madunes of various kinds. The iron mixed with the ore must be m large excess of the uantity necessary to chemically combine with the sulfur from the volatilizable metals in forming mono-sulfid of iron, (FeS.) and also an additional amount sufficient to saturate and form a slag with what silica the ore may contain; say for complex ores carrying forty parts zinc, about fifty per cent. of their wei ht of added iron is necessary to easily reduce and volatilize the zinc, and other metals of like nature; but it present process the quantity of 'going treatment.

may be more or less in quantity in case of different ores, as may be found necessary to decompose the ore mixtureand liberate the metals; but in all cases the added iron must chemically overbalance or be in excess of the requirements of the sulfur and silica. Such large per cent. of excess iron has been found to completely free the volatile metals so that they will not be carried into the matte, in part, and thus form a troublesome mixture for after treatment.

The iron employed may be ordinary machine shop waste, chips and filings, borings and turnings; the material known as iron sponge comminuted or iron in any equivalent granular form. This ore and 1ron mixture is'placed in a crucible, or closed retort, of any suitable form capable of being heated by external means, as by an inclosing furnace, or by a current of electricity, or by other means. The retort is connected with a condensing apparatus, which may be con structed as more fully hereinafter described.

The retort or crucible is closed, except for the leader to the condenser, and luted so as to keep out external air and avoid the forming of oxids of the metals while under- After the retort is charged with the ore and iron mixture andclosed, heat is applied in the manner above indicated and maintained at such temperature as may be necessary to liberate the metal, or metals, capable of being volatilized out of the ore, and the heating continued until they are driven off and the non-volatile metals have melted and united in the matte that is formed by union of the added iron and the sulfur present in the ore; which product, together with the slag, is then in cond tion to be discharged from the retort wlule still in a fused condition.

It will be understood that no carbon or reducing agentother than the iron is required, nor is anything added to the oremlxture for the liberating of the volatile metals while undergoing the process, the-iron chips or drillings acting both as a decomposing and as a reducing agent to free such metals. The iron also, together with the sulfur, acts as a carrier for gathering and concentrating the non-volatile metals into the matte produced within the retort-or crucible.

In some instances silica or lime may be added to the mixture to form a slag; or slag from a previous operation may be added n the crucible,

" nected with the interior of the retort or me1t-.

ture for the respective sections regulated or (lensing, .the sections their order, so that when a slag is deemed necessary to facilitate the working of some particular ores; but in mostcas'es it is unnecessary to add slag forming material other than those already present in the ore. U

' The matte produced by this improved process is nearly neutral in its action on the walls of the retorts, itnot having the firey, corrosive (aualities possessed by matte that is produce in blast furnace practice; hence its destructive action on the retort or crucible employed is slight.

The condensing apparatus for receiving.

the metallic fumes or volatilized substances as they pass from the retort, crucible or furseries of chambers or sections suitably coning hearthror crucible chamberby a conduit or leader through which the vvvolatile sub stances pass untilreaching a temperature of condensation. I

The different chambers orcondensing sec tion's are best maintained at different degrees of temperature, and the degree of temperaadapted for the particular kind of metal which the sectinn is predetermined for conbeing graduated in i will travel the farthestfrom the retortbefore condensing,

and thus be gained in-a purer condition than is possible whena single condensing section is In this way certain rare metals, like indium, or gallium, for instance; or others of a simi- Iar nature, if present in the ore, would be found in the more remote sections of the condensin apparatus. The condensing sections may e cooled by external means if desired; particularly iron-tubing or the like r is used for the more remote parts of it.

After the slag and matte are drawn ofi the retort is then recharged and the process:

steps gonethrough with as before; or the crucible can be provided with proper openings for entranceof the materials and dis-.

charge of the products, and the process thus ,made continuous instead ofintermittent;

' The accompanyingdrawin represents a sectional elevatlon diagram i ustrating in ageneral way the t form of apparatus which may be-used in order of arrangement of one 4 carrying out my process.

. condensers; 10-, 11

or other means of heating; 9

ln sa'ld drawing the numeral 1 represents retort, orfurnacej; a

Numerals 3, 4,15, 6 and 7 indicate the series of condensing sections or chambers connected by a leader 2 the cruclble; 8 indicates a nozzle for supplying a gas flame,

flue leading from the. furnace regulating. the temperature of the condensers; in the present instance bycontrollingdam- -more, the gain older processes.

the more-volatile metals used for all the metals .processes.

indlcates the beneath the and 12 indicate means for 'pers disposed in lines leading beneath the respective condensing sections into the stack 1 3. p

15 indicates a cooler or refrigerating means for regulating the remote section or downward part 7 of the condensing means, and 16 a di receptacle at the. end of the condenser con uit. It will be understood that in practicing my invention this or any other preferred form of apparatus can be employed; since myinvention relates to improvements in'the process or mode of treatment, irrespective of any particular form of apparatus that may same.

By the within described process of treating. volatile metals, it is possible to utilize ores in their natural condition, and by this means gain metallic elements which are usually lost in the ordinary processes; furtherof metal 1s more complete,

avoidingthe residual and other lossesof the The yield approximates closely to that found by assay, while the capacity of the jretorts is augmented by reason of the density of the ore mixture ascomared with the former methods; and further be used for working the 1t wholly avoids the roasting process hitherto necessary as a P m nary Step in the treat- -ment of such ores.

i It" will be understood that pure sulfur bearing oresrof any volatile metal can be very readily treated in the manner indicated and the metallic contents realized from them in much less time than is required byformer I In my process the non-volatile metals contained 1n the ores, such as copper, lead,-gold, silver etc. are concentrated in the matte in a condition for any further treatment desired,

An additional advantage of the rocess is the almost complete recovery oft e sulfur in the'matte, and from which it can be utilized by various means for use in the arts. 7

I do not claim broadly the employment of metallic iron-in the art of metallurgy irrespective of the manner in which it is em-. p oyed; but my invention has reference to the use of it in the. articular process and manner indicated, an for the purpose stated in my specification.

What I claim and ters Patent, i's y n 1. In the art of reducing complex zinc ores direct from the raw ore, the process step which consistsin sup lyingto the ore a uan- 'tity of finely divide metallic iron arge excess of the amount requiredto combine with the sulfur from the volatilizable metals in forming mono-sulfid of iron (FeS.) and an additional amount s cient to form slag, with the silica contained in the ore during the meltin operation.

. '2. T e rocess of treating sulfid ores containingvo atile metals, which consists in incontained in the oriwhich is concentrated desire to secure by Leti metals,

timately mixing with such ores a quantity of finely divided metallic iron particles in an amount of about fifty per cent. of the weight of the ore, thereby to chemically overbalance the sulfur that is combined with such volatilizable metals, then subjecting the mass to a degree of heat sufficient to volatilize said metals and set them free, forming monosulfid of iron with the sulfur previously combined with the metal, or metals, vola tilized out of the ore.

3. The improvement in treating zinc ores, which consists in adding to crushed raw zinc ore a quantity of finely divided metalliciron chlps in excess of the amount that can combinewith the sulfur in the volatilizable subjecting the mixture to heat in a suitable retort or furnace at a degree sufficient to drive off volatilizedmetals and melt the residual material to matte and slag, then vcondensing the volatilized metals in 'succhambers or sections, thecessively arranged temperatures of which are adjusted accord ing to the condensing requirements of the respective metals.

4. In the processof treating complex ores containing volatilizable metals, the improvement which 'consists in volatilizing such metals in a closed crucible or retort, leading the vaporized product from said retort into a series of condensing chambers or sections,

I regulating the temperature of the res ective sections each for the condensation o a 'pre determined kind of metal, and gathering and collecting the several metals in their respective sections.

j 5. The improvement in the process of recovering metal from complex ores containing zinc and rare volatilizable metals, as

l indium, gallium, or the like, which consists j in melting the ore, together with an excess of metallic 1IOI1, and volatilizing contained I metals in a suitable crucible or retort, carrying the fumes away from the fused product, and then condensing the volatilized metals,

such as indium, gallium and similar metals,

at a location separate from the zinc condensation.

6. In the process of treating ores containing volatilizable metals, the improvement which consists in fusing the ore and volatilizing the metals in admixture with an excess of metallic iron particles, and forming monosulfid of iron with the sulfur freed froinvthe matte produced.

ruary, 1907.

" GEORGE M. RICE.

Witnesses:

CHAS. H. BURLEIGH, S. P. MORRIS.

volatilized metals, and incorporating it in the W1tness my hand this 23rd day of F eb* 

